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[Andrei Alexandrescu]

Sergey Gromov wrote:
> Fri, 10 Oct 2008 08:22:10 -0500,
> Andrei Alexandrescu wrote:
>> Sergey Gromov wrote:
>>> My T[] is useful when you want to recursively split a megabyte file into 
>>> a couple thousands of tokens, and then modify some of those tokens.  For 
>>> that, your T[] must be lightweight, it must reference a bigger piece of 
>>> data, and it must guarantee not to write anything into memory outside 
>>> its boundaries.
>>>
>>> The Array is for appending.  It must always own its memory.  Therefore 
>>> you should be able to pass it around by reference, so Array is a *class* 
>>> and cannot be nearly as lightweight as T[].
>>>
>>> You see, many of their properties are orthogonal.  If you drop one, you 
>>> lose flexibility.
>>>
>>>> Besides, Array!(T) is not a good name for build-in type.
>>> Names are placeholders here, not an actual proposal.
>> What's wrong with making Array a library type?
> 
> Well, I'd like
>   new Object[15];
> to be immediately appendable and therefore a syntactic sugar for 
>   new Array!(Object)(15);

I have a nagging impression the syntax Array!(Object) strikes you as 
hard on the hand and the eyes...

Anyhow the syntax new Object[15] is idiotic because Object[15] is a type 
in itself. The syntax makes it next to impossible to actually generate a 
fixed-sized array dynamically.

In fact here's a challenge for you. Please generate a pointer to an 
Object[15] using new.

> I'd also like
>   "foo" ~ text ~ "bar"
> to become something like
>   (new Array!(char)) ~= "foo" ~= text ~= "bar"
> that is what Java does to string concatenation.  Sugar doesn't seem to 
> couple well with a purely library type.
> 
> Well, the latter is probably too complex and can cause major problems.  
> But new T[] should return something appendable.

I'm not 100% sure about that.


Andrei